The study looked at 11,536 adults from 2002 to 2011 with “very high” blood lead levels (BLLs), defined as equal to or greater than 40 µg/dL.

Wikimedia Commons / Thester11

Although banned in the U.S. in 1978, lead-based paint is still present in millions of American homes, putting contractors at risk.

Among the “very high” BLL adults with a known exposure source, occupational exposures accounted for 91 percent of the group. In addition, 19 percent of the group showed elevated BLLs for two years or more—a finding that CDC called “of grave concern.”

The data were drawn from CDC’s Adult Blood Lead Epidemiology and Surveillance (ABLES) program, which tracks elevated blood lead levels in U.S. adults.

Construction and Painting

Of 7,076 adults with high very blood lead levels whose known exposure source was their work, construction trades (comprised of painting and wallcovering contractors; highway, street and bridge construction; site preparation contractors; and other construction sectors) were one of the four largest categories represented, the data showed.

The other industries were manufacturing, remediation and other services, and mining.

Moreover, 49 percent of those 7,076 high-BLL adults hailed from just three NAICS occupational groups: painting and wallcovering contractors, nonferrous metal production and processing, and battery manufacturing, the CDC reported.

The painting and wallcovering contractors (NAICS Code 23832) accounted for 1,075 of the 7,076 high-BLL group exposed at work, putting them above the metal workers and below the battery manufacturers, CDC’s data showed.

NIOSH

A worker ladles molten recycled lead into billets. Battery manufacturing workers made up a significant share of workers with high blood lead levels.

(Painting, renovation and remodeling work also figured prominently in non-occupational exposure activities that caused high BLLs, CDC noted.)

Good News, Bad News

Significantly, the elevated levels persisted during a historical period that included a “remarkable reduction in environmental sources of lead, improved protection from occupational lead exposure, and an overall decreasing trend in the prevalence of elevated blood lead levels (BLLs) in U.S. adults,” the agency said.

In general, CDC reported:

Lead exposures “continue to occur at unacceptable levels”;

Blood lead levels are likely undertested and their results underreported; and

Lead levels once considered harmless are now known to have harmful effects, such as decreased kidney function.

The CDC designates 10 µg/dL as the reference BLL for adults; levels at or above that are considered elevated.

However, Occupational Safety and Health Administration lead standards do not require medical removal of a construction worker until his/her BLL reaches 50 µg/dL (60 µg/dL for general industry workers). And workers may return to work when their BLL falls below 40 µg/dL.

The study cited four case histories, including two painters, as examples of damaging occupational exposure.

Worker A: Bridge Painter/Blaster

Worker A, 48, worked for a bridge painting contractor and was responsible for recycling grit and steel shot from abrasive blasting operations. The worker used an air-supplied abrasive blasting hood for lead protection. CDC found that the worker had BLLs of 67 µg/dL in May and June of 2010.

CDC

An abrasive blasting clean-up worker in the study (not pictured) showed a blood lead level of 67 µg/dL. CDC considers a level of 10 or more elevated.

He was removed from all work and received chelation treatments (therapy to remove heavy metals from the body). His BLL dropped to 42 µg/dL in July and to 26 µg/dL in September. As of February 2011, he was still removed from work on his doctor’s orders.

Worker B: House Painter

Worker B, 46, was a painter for a small construction company who was seen in a hospital emergency room in December 2007 for severe stomach pain. His BLL was 143 µg/dL. At the time, the painter had been scraping paint from a house that was more than 100 years old with no respirator and no protective clothing except gloves.

“He was not informed about lead hazards,” CDC said. “His employer did not provide laundry services or disposable clothing. No other source of lead expsoure was identified.”

With treatment, the worker’s BLL was recorded at 13 µg/dL 27 months later.

Causes

The study cites a variety of reasons for the problem, beginning with OSHA standards that set action levels far above the blood lead threshold that the CDC considers elevated.

Four adults with very high blood lead levels (≥ 40µg/dL) in multiple years

CDC

The CDC also points the finger at:

Examining physicians who do not advocate for more stringent worker protections;

Employers who fail to implement or enforce sufficient engineering protections and workplace controls; and

Workers who fail to comply with safe practices.

Finally, CDC notes, the ABLES program lacks the resources to investigate and refer to OSHA every high-BLL case.

Reducing lead levels in American workers relies on turning all of these factors around, the agency says.